The present invention relates to a device for selectively activating a plurality of impaling pins such as might be used for separating and removing a strip from a paper web. Such a device is particularly useful in machines for forming sheets made up of several multi-sized paper webs such as might be done in the manufacture of mailers having sealed envelopes with one or more web inserts.
Mailers made from continuous formed envelopes having one or more web inserts are commonly used and eliminate the need to stuff and seal individual envelopes as well as the cost of purchasing and storing the individual components.
Several methods of manufacturing multilayer mailers are disclosed in U.S. Pat. No. 3,339,827 to Steidinger and in U.S. Pat. No. 4,512,256 to Schriber et al. A plurality of webs are preprinted in certain discrete areas and generally include material which will be the same from one mailer to another.
Each preprinted web is then cut transversely across its longitudinal extent at spaced locations between the preprinted areas to remove a strip extending from one margin substantially into, but not through, the other margin. The removed strip provides a slot in the web which is substantially equidistant between the preprinted areas and divides the web into individual and properly sized and positioned insert web portions, each containing the preprinted material.
The insert web portions from each preprinted web are then collated into insert web layers. Each web layer is positioned between a front web and a back web. Both front and back webs are wider than the insert webs and their outer perimeters are positioned and glued together to form individual envelopes containing the cut insert web layers.
The cutting, separating, and removing of the strip is normally performed by passing a web having the preprinted areas, between a pair of driven cylinders or rolls. One of the cylinders is adapted for mounting at least two rows of removable blades extending radially outwardly from and longitudinally of the cylinder. The rows are positioned such that the circumferential spacing between the blade rows equal the desired size of the strip. The cylinder is also adapted for mounting at least one row of impaling pins which are generally equally spaced between the rows of blades. The blade rows function to cut a strip in the web between the preprinted areas while the impaling pins puncture and impale or hook the strip to separate and remove the strip from the web.
The size of the strip is, of course, determined by the desired size of the web insert. Previous notch cylinder units have been designed to produce only one size of insert for a particular size mailer. For an example, previous notch cylinder units have been configured for either "2-around", "4-around", or "6-around" (2, 4, or 6 pairs of blade rows respectively), blade configurations which correspond to a particular insert size. Changing to another size insert and corresponding mailer, which is a multiple of the one size notch cylinder unit, requires replacing the entire notch cylinder unit. This represents a relatively time-consuming process, and requires keeping two very expensive and different sized units on hand.
What is needed, therefore, is a notch cylinder unit which is capable of producing two different sized inserts thereby allowing the user to easily change from one size mailer to another size mailer.